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W.J. Liss

Publications and source records attributed to W.J. Liss.

11 recordsLinked to original sources
USGS2008

Interaction between introduced trout and larval salamanders (Ambystoma macrodactylum) in high-elevation lakes

The larval stage of the long-toed salamander ( Ambystoma macrodactylum ) is the top vertebrate predator in high-elevation fishless lakes in the North Cascades National Park Service Complex, Washington (U.S.A.). Although most of these high-elevation lakes were naturally fishless, trout have been stocked in many of them. We sought to determine the effects of physicochemical factors and introduced trout on abundance and behavior of A. macrodactylum larvae. Larval salamander densities were estimated by snorkeling. Snorkelers carefully searched through substrate materials within 2 m of the shoreline and recorded the number of larvae observed and if larvae were hidden in benthic substrates. Physicochemical factors were measured in each lake on the same day that snorkel surveys were conducted. In fishless lakes, larval salamander densities were positively related to total Kjeldahl-N concentration and negatively related to lake elevation. Crustacean zooplankton, especially cladocerans, were important food resources for larval A. macrodactylum . Crustacean zooplankton and cladoceran densities were positively related to total Kjeldahl-N, suggesting that increased food resources contributed to increased densities of larval A. macrodactylum . Differences in larval salamander densities between fish and fishless lakes were related to total Kjeldahl-N concentrations and the reproductive status of trout. Mean larval salamander densities for fishless lakes with total Kjeldahl-N < 0.045 mg/L were not significantly different from mean larval densities in lakes with reproducing trout or in lakes with nonreproducing trout. In fishless lakes with total Kjeldahl-N ≥ 0.045 mg/L, however, mean larval densities were significantly higher than in lakes with reproducing trout where fish reached high densities. In fishless lakes with total Kjeldahl-N ≥ 0.095 mg/L, mean larval densities were significantly higher than in lakes with nonreproducing trout where trout fry were stocked at low densities. Reduced larval salamander densities in lakes with trout likely resulted from trout predation. There were no significant differences in the percentage of larvae hidden in benthic substrates between fishless lakes and lakes with fish. Our results imply that assessment of the effects of fish on amphibians requires an understanding of natural abiotic and biotic factors and processes influencing amphibian distribution and abundance.

Washington↗
USGS2000

Growth and diet of fish in Waldo Lake, Oregon

Waldo Lake, located in the Oregon Cascades, is considered to be one of the most dilute lakes in the world. Even with low nutrient concentrations and sparse populations of zooplankton, introduced fish in the lake are large in size and in good condition when compared to fish from other lakes. This apparent anomaly is due to the availability of benthic macroinvertebrates. Taxa found in the stomach contents offish captured in Waldo Lake consist primarily of Chironomidae larvae and pupae, Trichoptera larvae and pupae, amphipods, Ephemeroptera larvae, and Odonata larvae.

Oregon↗
USGS1998

Phytoplankton assemblages in high-elevation lakes in the northern Cascade Mountains, Washington State, USA

Phytoplankton assemblages in high-elevation lakes of North Cascades National Park Service Complex were studied during the open-water period in 1989. Collectively, 93 taxa were identified in 55 samples from 51 lakes. Based on cell densities, cyanobacteria had the highest relative abundance (36.7 %), followed by chlorophytes (29.8 %), and chrysophytes (19.6 %). Aphanocapsa delicatissima had the highest proportional abundance (14.0 %). Only 15.1 % percent of the taxa occurred in more than 20 samples. Phytoplankton cell densities increased following a gradient of increasing lake-water temperature, alkalinity, and concentration of total Kjeldahl-N with decreasing lake elevation. Chrysophytes and cyanobacteria were quantitatively (relative abundance) the most important taxa in alpine and subalpine lakes, whereas cyanobacteria had the highest relative abundances in high-forest and low-forest lakes. Chlorophytes had their highest relative abundance in high-forest lakes. Although low in relative abundance, diatoms and dinoflagellates were most abundant in alpine lakes. An ordination by correspondence analysis indicated that most alpine, subalpine, and high-forest lakes had similar floras. Although a few subalpine lakes exhibited deviations from this pattern, the main differences in phytoplankton composition were found in a group of low-forest and high-forest lakes. Canonical correspondence analysis (CCA) provided evidence that the distribution of samples and taxa in ordination space was correlated with a gradient of decreasing lake elevation and increasing water temperature, alkalinity, and concentration of nitrogen. When CCA was used to examine relationships among phytoplankton taxa and vegetation zones, a continuous distribution of taxa was found from the low-forest zone to the subalpine zone, with a large number of taxa occurring primarily in the subalpine and high-forest zones. Three phytoplankton taxa occurred primarily in alpine lakes, whereas five taxa co-occurred in alpine, subalpine, and high forest zones. Collectively, lake elevation and associated changes in water quality and concentrations of nutrients, especially nitrogen, appeared to be the primary physical and chemical factors influencing the taxonomic structures of phytoplankton assemblages.

Washington↗
USGS1997

Influence of basin-scale physical variables on life history characteristics of cutthroat trout in Yellowstone Lake

Individual spawning populations of Yellowstone cutthroat trout Oncorhynchus clarki bouvieri differ in life history characteristics associated with broad spatial and temporal environmental patterns, but relationships between specific life history characteristics of Yellowstone cutthroat trout and physical aspects of the environment are poorly understood. We examined basin-scale physical characteristics of tributary drainages and subbasins of Yellowstone Lake in relation to timing (peak and duration) of lacustrine–adfluvial Yellowstone cutthroat trout spawning migrations and mean length of cutthroat trout spawners in 27 tributaries to the lake. Stream drainages varied along gradients that can be described by mean aspect, mean elevation, and drainage and stream size. Approximately two-thirds of the variation in the timing of the peak of the annual cutthroat trout spawning migrations and average length of spawners was explained by third-order polynomial regressions with mean aspect and basin area as predictor variables. Because most cutthroat trout ascend tributaries soon after peak runoff, it appears that the influence of basin-scale physical variables on the date of the migration peak is manifested by the pattern of stream discharge. Spawner length does not seem to be a direct function of stream size in the Yellowstone Lake watershed, and aspect of the tributary basin seems to have a greater influence on the body length of cutthroat trout spawners than does stream size. Mechanisms that explain how the interaction of basin-scale physical variables influence spawner length were not investigated directly; however, we found evidence of distinct aggregations of cutthroat trout that are related to physical and limnological characteristics of the lake subbasins, and there is some indication that lake residence may be related to tributary location.

Wyoming↗
USGS1997

Using mark-recapture methods to estimate fish abundance in small mountain lakes

The majority of lacustrine fish populations in the western USA are located far from the nearest road. Although mark-recapture techniques are widely accepted for estimating population abundance, these techniques have been broadly ignored for fisheries surveys in remote mountain lakes because of restricted access and associated logistical constraints. In this study, mark recapture experiments were used to estimate fish population abundance in nine small (< 7 ha) lakes of the North Cascades National Park Service Complex. Fish in the mark sample were collected by angling, fin-clipped, and immediately released; fish were recaptured with variable mesh monofilament gill nets. A single-census Petersen estimator was used to calculate abundance in each lake, and assumptions for unbiased estimates appeared to be satisfied in most cases. Post-release mortality of angler-captured fish was low. The small size of these lakes in conjunction with the brief period of rime allotted for each individual experiment apparently reduced the probability of unequal vulnerability and mortality for marked and unmarked fish. Single-census mark-recapture experiments appeared to provide reasonable estimates of population abundance in these mountain lakes. Resulting estimates furnish a substantial increase in information when compared to more ubiquitous assessments of relative abundance, but the logistical requirements are modest. We believe that this technique may useful for survey purposes in other small, remote lakes.

Northwest Science↗
USGS1996

Distribution of nearshore macroinvertebrates in lakes of the Northern Cascade Mountains, Washington, USA

During the summer of 1949 studies were conducted at Princeton, New Jersey, to determine the effects on wildlife of DDT used in the control of Dutch elm disease. Direct mortality was determined by intensive search for dead birds after spraying. Twenty-six songbirds, one bat, and one gray squirrel were found. Of 11 dead birds from a study area of approximately 20 acres only one was an adult. Songbird populations were determined by censuses before and after spraying on a study area and on a similar unsprayed check area. The number of all breeding birds showed a 19.6 percent decrease on both the study and check areas during the week immediately following spraying. About two weeks after spraying the population in the treated area began to increase and within another week was back to prespray level. When only those species common to both sprayed and unsprayed areas are considered a population decline of 22 percent was measured in the sprayed area while the check area showed a 6 percent increase in numbers over the same period. Nestling mortality was studied in both areas. Among 18 young found on the study area during and following spraying 8 (44%) survived. Death of two broods of catbirds occurred four days after spraying. Of 21 young found on the check area 15 (71%) survived.

Archiv fur Hydrobiologie↗
USGS1994

Life-history organization of Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri) in Yellowstone Lake

Life-history organization of the cutthroat trout (Oncorhynchus clarki) may be viewed at various levels, including species, subspecies, metapopulation, population, or individual. Each level varies in spatial scale and temporal persistence, and components at each level continually change with changes in environment. Cutthroat trout are widely distributed throughout the western United States, occurring in such diverse environments as coastal rivers of the Pacific Northwest and interior streams of the Great Basin. During its evolution the species has organized into 14 subspecies with many different life-history characteristics and habitat requirements. Within subspecies, organization is equally complex. For example, life-history traits, such as average size and age, migration strategy, and migration timing, vary among individual spawning populations of Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri) in tributary streams of Yellowstone Lake. Understanding the effects of human perturbations on life-history organization is critical for management of the cutthroat trout and other polytypic salmonid species. Loss of diversity at any hierarchical level jeopardizes the long-term ability of the species to adapt to changing environments, and it may also lead to increased fluctuations in abundance and yield and increase the risk of extinction.

Canadian Journal of Fisheries and Aquatic Sciences↗